no-jira: remove edu backport of collections imports

src/main/java/org/olat/core/util/nodes/GenericNode.java

@@ -28,14 +28,13 @@ package org.olat.core.util.nodes;
 
 import java.io.Serializable;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
 
 import org.olat.core.logging.AssertException;
 import org.olat.core.util.CodeHelper;
 
-import edu.emory.mathcs.backport.java.util.Collections;
-
 /**
  * Description: <br>
  * 

src/main/java/org/olat/modules/docpool/ui/DocumentPoolAdminPermissionsController.java

@@ -20,6 +20,7 @@
 package org.olat.modules.docpool.ui;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
 import java.util.Set;
@@ -36,8 +37,6 @@ import org.olat.modules.taxonomy.TaxonomyRef;
 import org.olat.modules.taxonomy.TaxonomyService;
 import org.springframework.beans.factory.annotation.Autowired;
 
-import edu.emory.mathcs.backport.java.util.Collections;
-
 /**
  * 
  * Initial date: 13 nov. 2017<br>

src/main/java/org/olat/modules/lecture/ui/CloseRollCallConfirmationController.java

@@ -21,6 +21,7 @@ package org.olat.modules.lecture.ui;
 
 import java.util.ArrayList;
 import java.util.Calendar;
+import java.util.Collections;
 import java.util.Date;
 import java.util.List;
 
@@ -50,8 +51,6 @@ import org.olat.modules.lecture.Reason;
 import org.olat.modules.lecture.RollCallSecurityCallback;
 import org.springframework.beans.factory.annotation.Autowired;
 
-import edu.emory.mathcs.backport.java.util.Collections;
-
 /**
  * 
  * Initial date: 12 juin 2017<br>

src/main/java/org/olat/modules/lecture/ui/export/AbstractLectureBlockAuditLogExport.java

@@ -21,6 +21,7 @@ package org.olat.modules.lecture.ui.export;
 
 import java.io.IOException;
 import java.io.OutputStream;
+import java.util.Collections;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
@@ -44,8 +45,6 @@ import org.olat.repository.RepositoryEntry;
 import org.olat.repository.RepositoryManager;
 import org.olat.user.UserManager;
 
-import edu.emory.mathcs.backport.java.util.Collections;
-
 /**
  * 
  * 

src/main/java/org/olat/modules/lecture/ui/export/LecturesBlockPDFExport.java

@@ -21,6 +21,7 @@ package org.olat.modules.lecture.ui.export;
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -46,8 +47,6 @@ import org.olat.modules.lecture.LectureBlock;
 import org.olat.modules.lecture.LectureBlockRollCall;
 import org.olat.repository.RepositoryEntry;
 
-import edu.emory.mathcs.backport.java.util.Arrays;
-
 /**
  * 
  * Initial date: 22 juin 2017<br>

src/main/java/org/olat/modules/qpool/ui/QuestionItemAuditLogExport.java

@@ -22,6 +22,7 @@ package org.olat.modules.qpool.ui;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.math.BigDecimal;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.Date;
 import java.util.List;
@@ -46,8 +47,6 @@ import org.olat.modules.qpool.ui.metadata.MetaUIFactory;
 import org.olat.modules.qpool.ui.metadata.MetaUIFactory.KeyValues;
 import org.olat.user.UserManager;
 
-import edu.emory.mathcs.backport.java.util.Collections;
-
 /**
  * 
  * Initial date: 23.01.2018<br>

src/main/java/org/olat/modules/taxonomy/manager/TaxonomyLevelDAO.java

@@ -21,6 +21,7 @@ package org.olat.modules.taxonomy.manager;
 
 import java.io.File;
 import java.nio.file.Path;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.Date;
 import java.util.List;
@@ -48,8 +49,6 @@ import org.springframework.beans.factory.InitializingBean;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
 
-import edu.emory.mathcs.backport.java.util.Collections;
-
 /**
  * 
  * Initial date: 22 sept. 2017<br>

src/test/java/org/olat/resource/accesscontrol/provider/auto/manager/IdentifierHandlerTest.java

@@ -26,6 +26,7 @@ import static org.mockito.Mockito.when;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.List;
 
 import org.junit.Before;
@@ -37,8 +38,6 @@ import org.mockito.Spy;
 import org.olat.repository.RepositoryEntry;
 import org.olat.resource.accesscontrol.provider.auto.IdentifierKey;
 
-import edu.emory.mathcs.backport.java.util.Collections;
-
 /**
  *
  * Initial date: 14.08.2017<br>